Download The Acoelomate Invertebrates

BSC 2011L
Kingdom Animalia
All animals are multicelluar and
heterotrophic
 Some means of locomotion
 Always diploid
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Animal Taxonomy
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Domain Eukarya
 Kingdom Animalia
○ Invertebrates
 Parazoa – no true tissue layers
• Phylum Porifera – sponges
 Eumetazoa – true tissues, symmetry
- RADIATA – radial symmetry
• Phylum Ctenophora – comb jellies
• Phylum Cnidaria
• Class Hydrozoa – Portuguese man of war, Hydra, Obelia
• Class Scyphozoa – jelly fish
• Class Anthozoa – coral and sea anemones
- Bilateria – bilateral symmetry
• Flatworms
• Protostomes
• Dueterostomes
Animal Characteristics
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Symmetry
 Radiata – radial symmetry, diploblastic (2
tissues)
 Bilateria – bilateral symmetry, triploblastic
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Body Cavity
 Acoelomates – no cavity
 Psuedocoelomates – false coelom, not
completely lined by mesoderm derived tissue
 Coelomates – true coelom, room for organs in
body cavity lined with mesoderm tissue
 Protostomes – 1st embryonic opening becomes mouth
 Deuterostomes – 1st embryonic opening becomes anus
Body Symmetry
Phylum Porifera
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Live in water, mostly marine
No true tissues
Adults are sessile but larvae
are mobile - planktonic
assymmetrical
Can produce asexually and
sexually
Digestion – intracellular
choanocytes
Circulation – water transport
Phylum Porifera
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Animal:
Symmetry:
Body cavity:
Digestion:
Circulation:
Segmentation:
Appendages:
Nervous:
Habitat:
Respiration:
Excretion:
Locomotion:
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Support:
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sponges
asymmetrical
spongeocoel
intracellular choanocytes
water transport, amoebocytes
none
none
none
Aquatic, marine
diffusion
diffusion
none (sessile, however larvae are
flagellated)
spicules
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Spicules
http://www.deanza.edu/faculty/mccauley/6a-labs-sponges-01.htm
Phylum Ctenophora
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Radially symmetrical
True tissues
(diploblastic)
Move by cilia
Many are
bioluminescent
Phylum Cnidaria
Radially symmetrical
 True tissues (diploblastic)
 Two body forms: polyp and
medusa
 Part of zooplankton
 Reproduce sexually and
asexually
 Carnivores
 Digestion – gastrovascular
cavity
 Circulation – cells in direct
contact with water
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Phylum Cnidaria
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Have nerve net between 2 tissue layers
Cnidocytes
 Stinging cells
 Each one has fluid filled capsule called nematocyst
○ Contains thread that trap or sting prey
Phylum Cnidaria
Class Hydrozoa - Hydra
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Animal:
Symmetry:
Body cavity:
Digestion:
Circulation:
Segmentation:
Appendages:
Nervous:
Habitat:
Respiration:
Excretion:
Locomotion:
Support:
Hydra
Radial
coelenteron (sac)
gastrovascular cavity
cells in direct contact with water
none
tentacles around mouth
nerve nets
Aquatic
diffusion
none
limited
none
Hydra Model
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Obelia
http://faculty.clintoncc.suny.edu/faculty/michael.gregory/files/bio%20102/Bio%20102%20Laboratory/Animal%20Diversity/Porifera,%20Radiata/Sponges_through_Roundworms.htm
Phylum Platyhelminthes
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Flatworms
 Can be free living or parasitic
 Hermaphroditic
 Acoelomates
○ One opening
 Digestion – gastrovascular cavity
 Circulation – gastrovascular cavity
Phylum Platyhelminthes
Class Turbullaria
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Animal:
Symmetry:
Body cavity:
Digestion:
Circulation:
Segmentation:
Appendages:
Nervous:
Habitat:
Respiration:
Excretion:
Locomotion:
Support:
Planaria
Bilateral
acoelomate
gastrovascular cavity
gastrovascular cavity
none
none
brain, 2 ventral nerve cords, ladder-like
aquatic
diffusion
flame cells
muscles
none